Would I be able to replace my cat with straight pipe and still run good

 

Please don't; the lungs of everybody around you will thank you.

 

You'll set a code without more work. Most states will fail you with an emmision code.

The real question is "why" do you want/think you need to do this?

 

It is not advisable to remove the catalytic converter and install a straight pipe in its place. The engine was designed to run with a particular amount of back-pressure... removing the cat will alter/reduce the pressure